<em># package</em>
import 'package:flutter_web/material.dart';
<em># Widget 有状态的控件</em>
class <b>HomePage</b> extends StatefulWidget {
	final String title;
	<b>HomePage</b>({ Key key, this.title }) : super(key: key);
	@override
	_PageState createState() => _PageState(); // === createState()  => _PageState();
}
<em># page</em>
class _PageState extends State&lt;<b>HomePage</b>&gt; {
    @override
    Widget build(BuildContext context) {
		return Scaffold(
			appBar: AppBar(),
			body: Container()
		);
	}
}